* {
  margin: 0;
  padding: 0;
}
body {
  width: 100vw;
  height: 100vh;
  display: flex;
  background-color: black;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}
.scene {
  position: relative;
  /* 透视属性，数值越大越接近原始尺寸 */
  perspective: 17px;
}
.wrap {
  position: absolute;
  left: 50%;
  top: 50%;
  width: 1000px;
  height: 1000px;
  margin-left: -500px;
  margin-top: -500px;
  /* background-color: white; */
  transform-style: preserve-3d;
  animation: move 12s linear infinite;
}
/* 影分身 */
.wrap:nth-child(2) {
  animation-delay: -6s;
}
.wrap:nth-child(2) .wall {
  animation-delay: -6s;
}

.wall {
  position: absolute;
  left: 0;
  top: 0;
  height: 100%;
  width: 100%;
  background: url(../images/silver.jpg);
  background-size: cover;
}
.wall-left {
  transform: rotateY(90deg) translateZ(-500px);
}
.wall-right {
  transform: rotateY(-90deg) translateZ(-500px);
}
.wall-top {
  transform: rotateX(90deg) translateZ(-500px);
}
.wall-bottom {
  transform: rotateX(-90deg) translateZ(-500px);
}

.wall-back {
  transform: translateZ(-500px);
  animation: fade 12s linear infinite;
}
@keyframes move {
  0% {
    transform: translateZ(-500px);
  }
  100% {
    transform: translateZ(100px);
  }
}
@keyframes fade {
  0% {
    opacity: 0;
  }
  25% {
    opacity: 1;
  }
  75% {
    opacity: 1;
  }
  100% {
    opacity: 0;
  }
}
